The overall goals of this proposal is to continue to serve as one of the clinical centers in the National Institutes of Health Exploratory Trials in Parkinson's Disease (NET- PD) initiative and to continue participation in the large, collaborative, randomized, double blinded trials of neuroprotective agents in patients with early Parkinson's disease (PD). Our program represents a multidisciplinary, interactive, and collaborative group of investigators and clinicians who have long been committed to the study and care of individuals with PD and other related conditions. Our aims are as follows: (1) continue to recruit, retain, and follow PD patients, including woman and minority patients early in their clinical course per established protocols; (2) operate a clinical center to enroll, monitor, and examine patients per the protocols established by the coordination center; (3) adhere to common protocols, cooperate with other centers and the NINDS in order to conduct pilot and efficacy studies; (4) maintain an administrative structure to record, manage, maintain, and process clinical trial data while collaborating with the coordination and statistical centers, the IRB, NINDS scientific program personnel, the NIH oversight committee, referring physicians and lay groups; and (5) conduct research while ensuring safety of subjects and confidentiality of data.